Motor-compressor unit



1927. May 24 R. P. PESCARA MOTOR COMPRESSOR UNIT Filed June 5. 1925 3Sheets-Sheet 1 KQN 3. B @fm 1,629 927 May 24, 1927. R. P. PESCARA MOTORCOMPRESSOR UNIT Filed June 5. 1925 I5 Sheets-Sheet 2 Q :.3 I f a Q mf. ls,

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Lf/-f LN P. Pescara 1,629 927 May 24 1927 R. P. PESCARA MOTOR COMPRESSORUNIT Filed June 5, 1925 I5 Sheets-Sheet 5 `ing great careto make this inhantai Miy 24, i921.

UNITED STA TliiS PAUL PATERASl PESCARA, Ol' PARIS, FRANCE, ASSIGNOE T0THE PESCARA RAY- HOND CORPORATION, OF DOVER, DELAWAREA CORPORATION Ol'DELAWARE.

KOTOR-COMPRESSOR UNIT.

Application led June 5, 1935, Serial lo. 85,2%, and in France .Time 11,1984.

This invention relates to machines which are at the same time producersand transformers of energy, for example, motor compressor units.

The main object of the invention is to increase the efiicienc ofthecycles at resent employed in in ustr for the t rinodynamic evolution oft e gaseous masses intended for combustion or arising from combustion,in internal combustion engines, and forms, in a sense, an improvementand renement in the so-called two stroke cycle, whether combustion takesplace under constant volume or under' constant pressure.

The present invention consists essentially in carryin out the followinoperations inside a cy indr'ical space, w ose volume is made to var bythe alternating movements of a as-tig t piston arranged therein, saidcyli-n ricalspace havin a very great rat-io between the length and .t ebore: 4

l. Expanding the burnt ases arising from the combustion of `a comustible agent effected under constant volume or constant pressure, theexpansion being carried down to a pressure approximating that of thesurrounding atmosphere.

2. Causin the machine to suck in from `the atmosp 1ere a certain amountof ure air, which enters in the proximity o the combustion chamber andis drawn along' in the wake of the burnt gases, cooling the walls as itfollows the movements of the piston. V 4 il 3. Utilizing theY s eedacquired by this mass of air and b t e mass of burnt gases to cause theexpu sion of a portion thereof when the movement of the piston slackens.

4. Injecting at a low pressure, asuicient uantity of carburetted air, incase combustion is effected under constant volume, tak- 'ection in sucha way that, on the one hand t e burnt gases remaining at this moment inthe cylinder are. always separated from the carburetted air by a layerof pure air and, on the .other ,hand,lthat the mass of carburetted airinjected may never reach the burnt gases exhaust ports.

5. Terminating the expulsion of the burnt1 gases by means ofthe returnstroke of the piston, driving them afglainst the pure air whilecompleting the ling up with carburetted air, in the case of combustionunder constant volume, or with pure air, in the case of combustion underconstant pressure.

6. Compras-sin and forcin at low pressure a portion o the combine pureair and carburetted air, into the low pressure reservoir used for feedinthe motor durin the k riod of injection o carburetted air comustion'under constant volume).

0r compressin sure a portion o the pure air into the low pressurereservoir used for feeding the motor during the latter part of theperiod of the scavenging with pure air, if the combustion is effectedunder constant pressure.

7. Ccmpressing substantially adiabatically the carburetted gasesvremaining in the c linder to such pressure as may be deemed esirableand atwhich they will be i ited. If desired this com ression is carrieup to the point where sel ignition of the mixture is obtained, in thecase where combustion is effected under constant volume.

Or compressing substantially adiabaticaly the air remaining in theiylinder until the esired pressure is obtains in the case of combustionunder constant pressure, and injecting the atomzed combustible underpressure.

The invention thus generally described comprises a large number ofapplications to which the protection of the present patent will benaturally extendedz as also to any apparatusof any kind utilizing-itsprinciple, and to their selzrate arts.

The invention will casi y understood .by reference to the followingdescri tion and alsoto the annexed drawings, w ich however, are only"ven by'way of examp e.

Fig. 1 of said drawings is a longitudinal section of a motor "com ressorunit constructed inaccordance wit the invention.

Fi 2 and 3 are large scale sections showing e working of the device foropening the sturage valves.

Fig, Ybis a lar scale section showing part. of thev sturtin evice of theapparatus.

Fi 5 is a rge scale section of the cylinder cad closing the cylinder onthe ccm-Q presser side.

and forcing at low pres- Fig. 6 shows the cylinder in longitudinalsection alon a plane perpendicular to the plane on 1 and shows theinstallation of an oil injection device taking the place of the sparkingplug. y y

ccording to the invention, and more especially in accordance with theconstructions to which the drawings refer, supposing it is desired toconstruct a motor coinpressor unit, this 'can be done as follows or insome similar manner. In a fixed horizontal frame 10, a portion of whoseinterior is bored out, is arranged a cylinder 11 having an easy slidingfit in the frame 10. ,The cylinder 11 is closed at one end by a cylinderhead 12 ri 'dly connected,thereto, and at the other end y a head 13,mounted as will be explained later on. .A gas-tightpistonv 14 canreciprocate in the cylinder 11.

The com ination of the piston 14 and the cylinder 11 forms then anoscillating system such that the iston 14 can reciprocate in theinterior ofp the cylinder 11 while the c linder 11 itself canreciprocate in the rame 10.

The cylinder head 12 has two passages 14'- 15 to which correspond thevalves 16-17. whose movements are controlled by the bent rockin levers18-19, which are ivoted on the cy inder 11 and carry the rolllrs 20-.21coperating with the fixed cams 22-23.

e passage 15 communicates freely with the atmosphere. The passage 14'terminates in a tube 24, outside the cylinder and bent at a rightangle.V This tube 24 slides inside a fixed casing 25 in which it fitsforinin a gas-tight joint. The arrangement t us allows the interior ofthe oscillating cylinder 11 to be laced in communication with acarburetter 2g by means of the pipings 14' 2.4-25 and 26, this last onebeing fixed.

The' rocking lever 19 is `of t e ordinary type. The rocki lever 18 onthe contrary `ma be of at a read described in detail y ype y atent filedof in another application for even date herewith, Serial umber 35,250.lhis type of rocking lever controls the openm and closing of the valve16 when the-cylin er 11 moves in the direction of the arrow 151. 0n thecontrary, the valve 16 always remains closed and, so to speak, integralwith the cylinder 11 when this latter moves in the direction of thearrow 150.

The cylinderll' also has one or'more openings like those at 31. guardedby valves like 32, opening from within outwards, and kept closed bysuiciently strong springs such The valve 32 is controlled by a rockinglever 34 carrying a roller 35 co-o rating with a fixed cam 36. Thedrawing in Fig. 1 does not allow the arran ement of the rocking lever 34to be clear y seen, on account of the smallness of the scale. Therocking lever 34 has therefore been shown in Figs. 2 and 3, on a largescale, which allows the following explanations to-be easily understood.

The rocking lever 34 is formed essentially of a forged piece pivotedabout the axis 37 in lugs 38 cast on the cylinder. This piece carries afork 39 which acts on the head 40 of the valve 32 and a cylindricalextension 41 in the interior of which there moves a smallpiston 42having the form of a projectile.

0n the same axis 37 is mounted a pawl 43 which carries the axis 44 ofthe roller 35. y

The pawl 43 is constantly pressed against the cam by the spiral spring45 and a projection 46 of said piiwl can enter the interior of thecylindrical cavity 41.

It will be understood from a comparison of Figs. 2 and 3, that accordingto the position of the piston 42 in the cylindrical cavity 41 andconsequently of the projection 46, the rocking lever can be locked toits pawl, or can. on the other hand, remain independent thereof. In thefirst case (Fig. 3) the roller 35 on passing over the raised portion ofthe cam controls the valve. In the second case (Fig. 2), on thecontrary, the valve is not raised when the roller 35 passes over theraised portion of the cam. The operation of this device will beexplained later on.

The c linder 11 carries (F ig. 1) ,a further series o ports 47 capableofregisteri with corresponding openings 48 arranged in the fixed frame 10.All the openings 48 leadinto a peripheral passage 49 which opens at 50into the exhaust tube placed perpendicularly to the plane of Fig. i

Another set of ports 51 are arranged in the cylinder `11. These canregister with the openings 52 fin the fixed frame 10. Said openings 52are guarded by spring y held valves 53 and serve to place the interiorof the cylinder 11 in communication with .the compressed air reservoir54.

The cylinder head 13 (Fig. 5) is'provided with one or more)passages as55, whose opening into the interior of the cylinder is guarded by,automatic suction valves 56. These valves are arranged sothat the canlui open towards the interior, of the cy inder the pressure existing inthe passage 55 and the cylinder 11. In order to allow the at# mosphericair to enter through the passages 55, the frame 10 is provided withopenings as 57. which can register with the exterior mouths ofl the saidpassagesk55. The openin 57 are guarded by safety valves 58 w ose objectwill be explained later on.

The ignition of the charge is eected by a spark plug 59 (Fig. 1)connected by a wire 60 to a trip magneto 61. actuated by a pawl 62,which is pivoted to the cylinder 11 and movin therewith.

In addition to these essential devices the apparatus is further providedwith various accessory mechanisms which will now be described.

phare by a passage naamw .Starting device-The object of this mechanlsmis to automatically start the piston.

and the c linder and to cause them to correctly ma e their firststroke.4 It comprises the following parts:

A reservoir 63, of a predetermined capacity contains compressed air at`a suiiicient pressure which can, according to circumstances, be thesame as, or different from, the pressure of the air in the reservoir 54.It communicates `by the passage 64 with a chamber 65. closed at itslower end by the valve 66 and at its uppenend by tlie valve 67. Thesetwo yalves 66 and 67 are of the same diameter and are rigidly mounted onthe same spindle 68.

The valve 67 is arranged in a cylindrical recess 69 communicating withthe atmos- 70. In thecylindrical recess 69 it acts as a gas-tightpiston, that is to say, that when openor closed, it forms an obstacle tocommunication between the chamber'-65 ,and the atmosphere. 1t will beunderstood that the two valves 66 and 67 mounted on the same spindle 68act as a balanced valve when the pressure existing in the cylinder 11 isthe atmosphere pres- -sure' and that their lifting movement requires noeffort, whatever may be the pressure existing in the reservoir 63 and,conse uently, .in the chamber 65.

he valve 66 guards the. orfice71 arranged in-the fixed frame 10'. whichorifice 71 can communicate in certain positions o the cylinder 11 withthe slit 72 arranged in e this latter.

The reservoir 63 is also provided with a conduit 73 closed by a cock 74whose plug can be actuated by means of a lever 75. On the-other side ofthe cock" 7 4 is a small automatic valve 76 closing the orifice of theassage is orifice 77 thus allows of communication` between the reservoir63 (through the tube 73, cock 74 and valve 76) and a cylinder 78, whoseaxis coincides with that of A the spindle 68 of the valves 66 and 67.

In the cylinder 78 `there can move ,a gastight piston 79 rigidlyVconnected to the spindle 68 and pressed .downwards by 'a cahbrated sring 80.

. It wil be noticed that the recess 69'1is separated from the cylinder78 by a screw plug 81 and that there 7can be no communication Abetweenthem.

. A portion' of the valve 76 has been shown on a large scale in Fig. 4.11t `will be seen that the valve 76 has a micrometric hole 82, whichmoreover'opensinto another micrometric hole 83 drilled perpendicular tothe first and passing right through the valve 76.

The operation of the whole device wilihe explained later on. y

Auwz'liary rotative device (Figs. `IA and 5).-Although, in principle,

the apparatus only consume f this shaft shouldthe two successive shownin Fig. 1 does not need any kinematic connection or any transformationof movemeut, it has been recognized that it might be useful in certaineases to have available a shaft revolvin the number o reciprocations persecond of the piston and cylinder. It is to be clearly understood thatthis shaft is not in any way intended to transmit ener to the exteriorof the ap aratus, but to ing up o certain apparatus found in commerceand in a rotative form. Such, for example, are, centrifugal governors,revolution counters which, in the resent case, may be utilized formeasuring t e number of reciprocations, oil or water pumps,'diagramrecorders, etc. To sum up, it is a question then of a device which'isnot essential to the workin of the mot-or compressor unit, which shoulan, exceedingly small amount of power in comparison with the power usedinL compressing the air, but which 4may be convenient for studying theoperation of the machineand for applying to it certain indispensablemeasuring and regulating apparatus. Intbe case of the Vmotor compressorunit shown in Fig. lof the drawings, care hasbeenftaken to so constructthe auxiliary rotativ element that the oscillatory movements of thecylinder 11 shall be in nov wav hampered? bythe connection between it ata speedl proportional to a low of the linkand the "revolving shaft. Itis desirable that have a fairly unifor'm speed of rotation, `but on theother handsthe oscillations of the cylinder, supposing it to beperfectly free wtould take place according to a kingmatic law which itis too diicult to combine with any simple mechanism. A mixed solutionhas therefore been adopted 'and a kinematic coupling device employedsuch, t` at, supposing the shaft turns uniformly, the movementof thecyl-- inder 'would closely approach the'theoreticalY movement it wouldhave if it were perfectly free. This theoretical movement ischaracterized by considerable accelerations at the beginning and end vofthe strokes and above all by a great-dierenee in duration betweenAstrokes which form one complete oscillation. l y. The cou ling deviceis therefore lnecessarily of tlieso-called quick return type. of whichvarious formsare Vordinarily employed inr machine tools such asplaning'` machines, shaping butit presents i'nthis case the peculiaritythat, conversely to what happens in machine tools, it is here the shaftwhich is driven instead of being the driving member.

machines and the like, p

On the other hand, as the( movements Y the device, so 'as to reventthetransmission of any considerable amount of power to the exterior of theapparatus, which would have the effect of considerably diminishing themechanical etliciency of the machine. f

Fig. 5 is a section on a large scale of the cylinder head 13 and of thekinematic connections of the cylinder 11 and with the aid of which thefollowing explanations will be easily understood.

In the cylinder head 13 is provided a cylindrical cavity85in which isarranged an axis 86 carrying two stops '87 and 88 between which ya.pring 89 1s compressed by means of a nut 90. The whole is cn- -closedin the cavity 85 by means of a threaded tube 91 forming an abutment forthe stop 88, whereas another tube 191 forms an abutment for the stop 87.The axis 86 is rigidly connectedl to a cylindrical piece 92 which has aneasy sliding tit inside the sleeve 91. -T'his piece 92 has a transverseaxis 93 on which is pivoted the foot of connecting rod 94.

The connecting rod 94 is also pivoted at its other end 95Ato the lugs 96which are connected to a lever 97. The latter is itself pivoted around aiixed hollow axis 98 mounted in Aa casing integral with the generalframe of the apparatus 10.

Besides this, said lever 97 is in form generally tubular and a piston,composed of two pieces 1D0-101, slides therein.

A crank 102, rigidly connected to the shaft to which the uniform rotarymovement isre uired to be given, has its crank pin 103 eld between thetwo halves 10G-101 of the piston and it is capable of passing throughthe lever 97 in which slots such as 104 have been made for this purpose.

The crankshaft 102 actuates acentrifugal governor 225eacting through therod 126 on the throttle valve 127 of the carburetter 27 Stabilizationdevice-lt is also necessary to redress perturbations which may occur inthe movement of the apparatus and this is the object of the followingstabilization device, whose operation will be explained later and whichis shown in Fi 5.

On the bottom of the cylnterhead 13 there is fixed by means of severaltubular lthe inside of the bolt 105 and the screw bolts such as 105-106,a small reservoir of compressed air 107. This reservoir 107communicates, on the' one hand, through passages 108 and. 109 with theinterior of he cyl-r inder 11,.A This communication can be 1nterceptedby means of an' automaticwalve 110v held on its seat by aspring 111. Q

On the other hand the reservoir V107 is provided with a flexible tube135 fixed to the lever 97 and communicatin with a passage 112 arrangedinside of t e said lever x 97. The hollow axis 98 is an orifice 113which is ca a ing with the orifice 114 ol) t when the lever 97oscillates round axis 98.

Finally, it will be seen in Fig. 1 that the hollow axis 98 communicatesthrou h its interior, by means of a tub'e 115, wit the reservoir ofcompressed air 54.

iS'afefy device-It has been necessary to foresee also the case of acollision between the piston and the cylinder, on the side of thecylinder head 13.

"Fig, 1 shows, to prevent this, several Belleville rings 116 arranged ina recess 117 provided for this purpose in the iston 14. T heseringsbear, on the-one and, on a piece 118 acting as a buffer and, on thee of registerhe passage 112 its bllimviaed with' other hand, on the bodyof the piston 14 anisms falling into the interior of the cyl,

inder 11.

On the other hand, the cylinder head 13 (Fig. 5) is a conical' part 121,which ensures the tightness of the joint, and b a cylindrical part `122.Behind the cylindbr head 131are arranged several other Belleville rings123, by means of which and the cover 124, the cylinder head 13 abutsagainst the cylinder 11 by means'of the threaded ring 125.

It will be easily understood that in case of a collision between thebutler 118 of the piston 14 and the abutment 119 ofthe cylinder head 13,the Belleville rings 116 and 123 will act as shock absorbers and preventdamage to the machine.

Oil injection. deviene-In case itis des'ired' to realize a combustionecle instead-of an explosion cycle, the sparliY lug 59 can be replaced byan injection evice for fuel under pressure. This device 128 which has nshown diagrammatieally in Fig. 6- has' nothing novel as regards its oration. It is fed with oil under pressure y a Hexible tube 129.

.The iiijection'nozzle 130 ends in head 131 which meets, at the end ofthe stroke of 'DI adjusted to the cylinder 11 by.

lll

the cylinder 11, a'ixed stop 132 whose po- 4'towards thecylinder head13, is llush with the ports 72 of the cylinder 11. This can can beregulated by means of the be done with the aid of a marked rodintroduced into the cylinder 11 by the opening for the spark lug 59.Through ythis same opening a litt e gasoline in injected intothecylinder 11'.

The piston 14 being positioned, the cylinder 11 is brought into aposition marked beforehand, so that the openings 71 and 72 are incommunication.

The lever 75.is then actuated so that the i cock 74 brings the tube 73into communicadriven uplwardly.

tion with the cylinder 78. The compressed air of the reservoir 63 raisesthe valve 76 and acts then on the piston 79 which is The valve 66 givespassage to t e com ressed air from the reservoir 63, which lEills thespace included between thepiston 14 and the cylinder head 13,.

The piston 14 is then drivenin the direction of the arrow 150 and thecylinder 11 in the direction of the arrow 151.` The compressed airinjected between these two parts expands. The pressure falls rapidly tothe atmospheric pressure. The spring 80 tends then to bring -back thepiston 79. to its original position driving before it the air lilhng thecylin er 78. This air can` only be expelled through the micrometricopenings 82 and 83 because the valve 76 has, at this moment, fallen backon its seat. The valve 66 thewfalls back slowly also on to its seat andso closes the communication between the reservoir 63 and the cylinder11.

It will be understood that the device gives the following main results:

1. The opening of the orifices 71 is accomplished very rapidly and at aspeed al-l most inde endcnt from the manner in which the lever 5 isactuated. Y

2. The time during which "the injection of compressed air takes place isalso independent from the manner in which the leveris acted on. Thistime depends solely on -the calibration of the spring 79 and the sizeand shape of the micrometric orilices 82 and 83.

,. 'the cylinder 1/1 with the necessai- D 3. Finally, it will beunderstood that'it is easy to regulate once for all the starting aparatus' for a certain initial pressure in t e reservoir 63, so astopstart the piston 14 and and lppropriete` force, which force is a Wayst e The piston 14 and the cylinder 11, having been started as justexplained, compress,- between them the air in the cylinderspace'engasoline charge closed between the piston 14 and the 'linderhead 12. In the proximityk of the dea point, thexpawl 62 acts on themagn flashes1 in the s ark plugfrQ, igniting4 the compressed air.

From this instant on the motor compresser unit is in its normal workingcondition and we shallnow study what takes place `successively in eachstroke, and on eto 61. A spark f each side of the reciprocation.

Forward stro/ce.

Motor aider-The explosion forces the piston 14` in the direction of thearrow 151 and the cylinder 11 in the direction 150. The expansion of the.burnt'gases goes on until the moment when the piston 14 reaches theexhaust ports 47, the pressure in the cylinder then being approximatelyequal to that of the surrounding atmosphere.

The ports 47 and 48 begin to coincide at the moment when the pistonpasses over them and at the same time the cam 23, acting on the valve17, opens the orifice of the passage 15. Y

The movement of the piston 14 continues, but with a tendency to slacken,so that the burnt Vgases following itv begin to escape through theopenings 47 by reason of t e speed they have acquired behind the piston.

t the same time an indraught of air is caused through the passages 15,which scavenges the burnt ases still remaining in the cylinder. Thispure air acquires also piston, during a complete" a certain speed whichresults in causin it to continue Aits scavenging movement, uring thewhole of the movement of the piston in' the .direction 151, between theopenings47 and the dead point.

During this forward stroke, the valveJ 32 is not lifted because at themoment of explosion the cylinder suddenly starts in the direction ofthearrow 150, the result being that the piston 42' is made to slide intothe position shown in Fig. 2. Therefore, when the roller 35 passes overthe raised portion of the cam 36 the pro]ection 46 cannot actuate therocking lever 34. On the other hand, the spring 33 is suilicientlystrongto prevent any movement'of the valve 32 due to the effect of theexpandin gases.

However, on arriving at t e en of the stroke, the acceleration of thecylinder 1s reversed, and the piston 42 tends b its inertia, to continueits motion in the irection of the arrow 150 since, at that moment, tl eroller 35 has alread assed the raised rtion of `the cam, an t e pawl 43,there oie, vis raised by the spring 45, and the piston 42 can passyunder the proection 46 4and finally 'occupies the position s own inFig. 3.

The valve 16 has also remained on its seat,

its mechanism being similar to that of thev valve 32. l y Compressorsida-The movement ofthe pston,14 and c linder 11 has a result, the

lio

compression at rstand afterwards the discharging, through the orifices51 and 52, to the reservoir 54, of the air which filled the c linder 11at the beginning of the stroke. rIl'his air has not been able to escapethrqu h ,the exhaust orifices 47 because these o y the openings 48 whenthe face of the piston towardsthe head 13 has already passed theopenings 47.

vIt isadvantageousto so calculate the apparatus that the damping of thereciprocal movement of the cylinder 11 and the piston 14 takes placeduring the dischar e ofthe compressed air. That is to say, t e move1ment of these parts ceases when their kinetic energy has yroduced thenecessary work of discharge. he advant s of this arrangement will beexplained 1n connection with the operation of the stabilization device.

It will be noticed that iii case of breaka of a valve su'chas 56, a lare portion of t e air contained in the cyliner 11 would be driven out atthe beginning of the stroke, through the passage 55 then communicating`through the openings 57 Vwith the atmosphere. Under these circumstancesa very violent collision might take place between the piston 14 ,and thecylinder head 13. Althou h considerably deadened by the collision evicelabove described, it might still be feared that such a 4violent'encounter might cause serious damage to the machine.

The object of the safety .valves 58 is precisely that of avoiding anescape of air by the'paages 55 and t e openings 57 which they closedirectly any air current, however insignificant, comes to pass. Underthese circumstances the breakage of an intake valve no longer gives riseto a serious accident.

, Return stroke. Uo/mpreasor aida-The cylinder 11 is forcedback in thedirection of the arrow 151 and the piston in that of the arrow 150 bythebull'er of compressed air which is at the pressure of the reservoir54 and has remained imprisoned between the piston 14 and the cylinderhead 13 at the moment the movement has 4 When this bu er expands, itsener transforms itself into kinetic energy for t e iston and cylinder.When the expansion as been carried tolapoin't slightly below theatmospheric (pressure, the automatic valves 56 o n lan ermit theatmospheric air to 'illA t e cylin er .11, because at this moment,'owing to the movement of the cylinder 11 in the direction 151, thepassages 55 communicate. with the atmbsphere through the openings 57.

Just as in the forward stroke, there can be no communication with 'theexhaust assage 50 because the ports 47 cease to register with theopenings 48 as soon as the face of the piston opposite the head 13reaches the ports 47.

Motor aida-The piston begins by driging before it the burnt gases whichhave followed it in its movement (in the direction 151 beyond theopenings 47. j t Y ese burnt gases are forced td escape through theports 47 because they encounter, opposite these ports, the current ofpure air coming from the bottom of the explosion chamber.

Moreover, during the stroke of the piston 14 (in the direction 150)between the dead point and the exhaust orts 47, the valve 16 opens andallow a ric ily carburetted current of air to ass. The exact moment. forthe opening o said valve 16 is determined experimentally so that, on theone hand, the gaseous current to which it gives passa e may sustain themovement of exhaust of t e burnt gases mixed with the scavenging air andthat, on the other hand, said gases may remain isolated from said ports47 by a sutlicient layerof pure air, up to the moment of the closing ofthe ports 47.

The movement .of the piston 14 and of the cylinder 11 continuing, theports 47 close immediately the piston passes them. The valves 16 t enalso close in turn.

There is then produced in the cylinder s ace included between the piston14 and t e cylinder head 12 a slight compression of the gaseous mixturetherein enclosed. 'At this moment the storage valve 32 lifts, beingactuated `by the cam 36, the piston 42 bein held by the projection 46 inthe position o Fig. 3. A portion of the gaseous mixture is driven intothe storage reservoir 154 through the tube 153, having a slidingvfitwith respect to said reservoir. The reservoir 154 is carried by aportion of the fixed frame 10, or some other relatively fixedstructure.l The carburetor 27, tube 26, and cams 36, 22 and L'23 are allsimilarly 'supported? y i It should further be noticed that the storagereservoir 154 communicates by a tube 155 with the carburetor 27..Therefore, this same gas, sutliciently enriched with combustible will beused in the injection ofhighly carburetted air, which ingecton takesplace through the passage 14' uring the next return stroke.

The storing, as carried out in this apparalllil tus, causes therefore noloss ofrcombustible.

When the piston 14 passes before the opening 31, the valve 32 fallsbac-k on toits seat owing to the setting `of the cam 36. 'lhecarbui'etted gases remaining in the cylinder space are then stronglycompressed up to t eir ignition, which may be produced either cto 61 bythe s ark plug 59 and the ma Iby the pawl 62 in the proxgitrhity ofoint, or by a compression carried iai expansion of the burnt lill of thecam 36, said piston is able to pass under the projection 46 and to takeup the position shown in Fi 2.

The devices for auxiqiary rotation and security aainst shocks have beensufficiently explaine reviously and it would be superfluous to well no'won their mode of operation. Operation of the' stabilization le/vice.-The foregoing explanations have disclosed the normal operation of themotor compressor unit. In practice, in view of the complete liberty leftto the movements of the cylinder 11 and the piston 14, it has to beconsidered what would happen in case something arose to disturb theoperation of the apiaratus.

t must first be remarked that, in the forward stroke (direction of thearrow 150 for the cylinder and 151 for the iston 14) the movements ofthe iston and) cylinder have been so calculate that the work of ases, atfirst transformed partially into kinetic energy of the oscillatingparts, is found again in the end under three forms: work of compression,work of discharge into the reservoir 54, work stored up in the buffer.

A similar balance for the return stroke direction 151 ufor the cylinder11 and 150 or the piston 14)` shows that the work of expansion of thebuffer should be equal, or verytnearly so, to the Work of storage andcompressionpreliminary to the explosion of the gases intended forcombustion.`

If any accidental cause lshould arise to upset these balances the piston14 and the cylinder 11 will perform abnormal strokes, whose amplitudeand frequency will be different from those provided for in thecalculation of the apparatus.

supposing, for exam le, a sudden and accidental enrichment o theexplosive mixture, the following phenomena will take place. Y

First forward stroke: The piston receiving a greater impulse than thatprovided for willveompress the buii'er at the end of,

its stroke with a pressure higher than the compression pressure, that isto say, higher than that in the reservoir 54.

First return stroke: The piston will be returned towards the 'cylinderhead 12 by a too powerful butler; at the end` of its stroke it willimpart an exaggerated compression to the explosive mixture. Theexplosion thus produced will be still more violent than its predecessor,etc.

If the effects of a sudden and accidental impoverishment of theexplosive mixture are studied. the following conclusions will be arrivedat. ,y

First forward stroke: The piston 13 will not have received sufficient ergy to discharge from the cylinder 1l lntothe reservoir 54 the expectedquantity of compressed air. At the end of its stroke there will remaintherefore an air buil'er which will have,

it is true, the pressure in the reservoir 54,

a gerated iniipul e owing to the volume of air in the bu avin beenincreased while its pressure has remained equal to that in the reservoir54. At the end of its stroke the piston will compress the explosivemixture to too great a pressure.

It is seen therefore that the consequences of a diminution in the forceof the explosion are, by the end of an oscillation, exactl the same asthose due to an increase in suc force. t

The Vabove given ex lanations have shown that the operation o the aparatus, as so far described, is unstable. n other words, and to sum up,if any disturbing cause should arise to upset thenorznal operation ofthe oscillating system, evenif. this cause should immediately disap ear,said oscillating system would not ten of its own accord to return to itsequilibrium. but on the contrary would tend to depart from it more andmore.

The stabilization device which has been described is intended toA remedythis drawback. It will now be explained how it works, supposing a suddenand accidental increase in the force of the explosion should take place.'The case of a diminution in such force need not be considered, as itresults, in the following oscillation, in an increase of the preliminarycompression and, finally, in an increase in the force of the explosion.

Suppose that the piston has been driven in the direction of the arrow151 and the cylinder in that of the arrow 150 by the expansion of burntgases arlsmg from an abnormally, rich charge.

The piston 14 and the cylinder 11 will. to l a certain extent passbeyond the position corresponding to Atheir theoretical dead oints.-Consequently, the bu tl'er compressed between` them `will be, as alreadyexplained, at a greater pressure than that 1n the reservoir 54.

:But when the pressure of the compressed air exceeds the normal comression pressure, the Vvalve 110 (Fig. 5) lits, and puts the dead spaceof the cylinder 11 into Fcommunication .with the auxiliary reservoir107. Thisdatter, is absolutely isolated atthis moment from the exterior,as the lever 97 occupies -theposition shown in Figure 5, and the orifice114'. is not opposite4 the orifice 113.

Under these circumstances` the oscillating parts absorb the excess of-kinetic energy,v

lun

not through the work of com ression of the buffer comprised in the cyinder 11, but through a work of compression acting both on the air insaid cylinder and on that in the auxiliary reservoir 1.07. i

When the movement of the oscillating system stops and reverses, thenon-return valve 110 closes' the passage 109 and the only buffer which,on expansion, can act on the piston and cylinder is that remainin in thecylinder 11 betweenV the piston 14 and the cylinder head 12, at themoment when the valve 110 has fallen back on its seat.

The piston 14 and the cylinder 11 perform therefore their return strokeunder the impulse of a buler of lesser mass than the normal buffer, butwhose ressure is, on the other hand, superior to t e normal. easy toimagine that the expansion of such a buii'cr mav be equivalent to thatof the theoretical butler and that, consequently, the operations of thereturn stroke can be correctly performed.

As a matter of fact, a detailed calculation shows that, as a generalrule, the deadening of the abnormal oscillation andnthe return to thetheoretical operation are not achieved in one single stroke, but, if thecapacity of the auxiliary reservoir 107 has been suit-ably chosen, as afunction of the normal roluine of the dead space, stability of operationof the apparatus is obtained; any disturbance in the normal operation ofthe apparatus is corrected in a small number of oscillations.

It should be noted that during the return stroke of the piston 14 andthe cylinder 11, the lever 97 swings in the direction ofthe arrow 151under the influence of the con necting rod 94. At a given moment, theopenixgs 114 are in registry with the 113. ,ommunication is thusestablishe be tween the auxiliary reservoir 10ir and the' reservoir' 54by -means of the passages 136 112 and 115. In this way the pressure ofthe air contained in the .rese voir 107 is automatically brought back tot e compression pressure which is also, it must not be for tten, that ofthe normal bu'er. The

devlce is thus ready to work again normally,

described, in place of the spark plug 59.

The carburetter 27 will be removed and a direct communication will heestablished between the reservoir 154-and the tube 26.

Oil injection takes place at the end of the compression stroke of thepiston and linder, the cylinder 11 moving as already e- `for injectingat a low .of

-scribed in the direction @of the arrow 151 and the piston in that ofthe arrow 150. The injection needle 130 is raised at the end of lthestroke when its head 131 comes into cony of4 the rest of the motor comressor unit in `,this case, all its parts, with t 1e exception of theomitted carburetter 27, operating under similar conditions to thosedescribed above for the explosion cycle.

Y I claim:

1. In an apparatus comprising a cylinder and a piston reciprocating insaid cylinder the combination of means for permitting expansion of burntgases down to a pressure approximately that of the surroundingatmosphere; means for sucking in from the atmosphere a certain quantityof pure air which enters the cylinder in the proximity of the combustionchamber and is drawn along in the wake of the burnt gases; means forinjecting at a low ressure, in the wake ot' the pure air previouslyintroduced, a`

suitable quantit carburetted air, in such a way that on t e one hand theburnt ases remaining at this moment in the mac ine are separated fromthe carburetted air by a cushion of pure air, and on the other hand thatthe carburetted air can never reach the exhaust ports of the machine;means for simultaneously expellin the burnt gases from the cylinder,whic expulsion is produced both by the speed acquired by the burntgases, as they follow the movement of the piston and also by the returnmotion of this latter which vterminates said expulsion; means forcompressing, at al low pressure, and discharging from the c linder apart of the fresh gas previously a mitted, a storing reservoir intowhich said fresh gas is discharged at a low pressure, whose contents,suitably carburetted, are used to produce the injection of carburettedair at the aforesaid low pressure; means for com ressin the gasesremaining in the cy inder and means for electrically igniting thecompressed mixture.

2. In an apparatus comprising a cylinder and a piton reciprocating insaid cylinder the com mation of means for permitting expansion of burntgases down to a pressure approximately that of the surroundingatmosphere; means for sucking in from the atmosphere a certain uantityof pure air which enters the cylin er in the proximity of the combustionchamber and is drawn along in the wake of the burnt gases; meanspressure, in the wake the pure air previously introduced, a` suitablequantity o carburetted air, in such pressure,

one '4 hand the burnt Vof. this latter which terminates said expulsion;means for compressing at a loyv ressure, and discharging from the cyliner a paitof the resh ga s previously admitted,

a storin reservoir into which said fresh gas is dischargd at a lowpressure, whose contents, lsuita ly carburetted, are used to produce theinjection of carburetted air at the aforesaid low pressure; means forcompressing the gases remaining in the cylinder, to such a pressure thatself ignition of the char e is produced.

3. n an apparatus comprising a cylinder and a piston reciprocating insaid cylinder, producing motive energy on one and the same side of thepiston, by the combination of means for permitting expansion of burntvases down to a pressure approximately that of the surroundingatmosphere; means for sucking in from the atmosphere a certain quantityof pure air which enters the cylinder in the proximity of the combustionchainber and is drawn along in the wake of the burnt' gases; means forinjecting at a low in the wake of the pure air previously introduced, asuitable quantity o carburetted air, in such a way' that on the gasesremaining at this moment in the machine are separated from thecarburetted air by a. cushion of pure air, and on the other hand thatthe carburetted air can never reach the exhaust orts of the machine;means for simultaneously expelling the burnt gases from the cylinder,which expulsion is roduced both by the speed acquired by t e burnt gasesas they'follow the movement of the piston and also by the return motionof this latter which terminates said expulsion; means for compressing,at a low pressure, and discharging from the cylinder a part admitted, astoring reservoir into which said fresh gas is discharged at a lowpressure, whose contents, suitably carburetted, are used' to produce thein'ection of carburettedair at the aforesai low pressure; means forcompressing the gases remaining in the cylinder and means forelectrically ignitingthe compressed mixture; and means for admitting,compressing and discharging air on the non-motive sidei of the piston.

4. ln an apparatus comprising a cylinder and a piston reciprocating insaid cylinder, producing motive energy on one and the dof of the freshgas previously,

same side of the piston by the combination of means for permittingexpansion of burnt gases down to a pressure ap roximately that thesurrounding atmosp ere; means for sucking in from the atmosphere acertain quantity of pure air which enters the cylinder in the proximityof the` combustion chamber and is drawn along inthe wake of the burntgases; means for injecting at a low pressure, in the wake of the pureair previously introduced, a suitable uantity of carburetted air, insuch away liiiat on the one hand the burnt gases remaining at thismoment in the machine are separated from the carburetted air by acushion of ure air and on the other hand that the car urette air cannever reach the exhaustports of machine; Imeans for simultaneously exelling the burnt gases from the cylin er, which expiosion is producedboth by the s ced acquired by the burnt gases, as they ollow themovement of the piston, and also by the return motion of this latterwhich terminates said expulsion; means for compressing at a low pressureand dischar ing from the cylinder a part of the fres 'gas previouslyadmitted., a storing reservoir into which saidrfresh gas is dischar edat a low pressure, whose contents, suita lv carburettcd, are used toproduce the injection of carburetted air at the aforesaid low pressure;means for com ressing the gases lremaining in the cylin er to such apressure that self ignition of the charge is produced; and means foradmitting, compressing an discharging air on thenon-motive side of f thepiston.

5. In an apparatus comprising a frame, a cylinder and a pistonreciprocatin in said cylinder said cylinder being mec anically free toreciprocate with respect to said frame, a distributin device for theports of said cylinder, said device comprising `a valve for one of saidports, a rocking lever pivoted to the cylinder, a fixed cam, a pawlpivoted to said lever and cooperating with said cam, a lockingsmemberfor locking said pawlto said lever, said locking 111cm-, ber bein freeVto slide by inertia in said rocking ever in a direction parallel tothat of the cylinder.

6. In an apparatus comprising a frame, a cylinder and a piston cyiinder,said cylinder being free torecipro-d cate in the frame, a port in thecylinder, a valve in the port, and means for operatin the valvecomprising a rocking lever pivote on the cylinder, a fixed cam, a pawlpivoted on the lever, a` spring for holding one end of the pawl inengagement with the cam, a passage in the lever, and a member free toslide in this passa e in a direction substantially parallel to t emovements of the cylinder, a portion of the pawl moving into and out ofthis passage as the pawl follows the the l reciprocating in the 'travelto this end of contour of the cam, whereb the pawl is free to moveindependently of t e lever when the sliding member is at one end of thepassage and out of the path of movement of the pawl. but the pawl andlever are locked againstindependent movementA when the member is at theother end of the passage.

7. In an apparatus comprising a frame. a cylinder and a pistonreciprocating in the cylinder. said cylinder being free to reciprocatein the frame, a port in the cylinder. a valve in the port, and means foroperating the valve comprising a rocking lever pivoted on thecylinder.\a fixed cam. a paw] pivoted on the lever. a spring for holdingone end of the pawl in engagement with the cam, and a member thrown byits own inertia from one position to another by the movements of thecylinder. this member being in the path of movement of the pawl in oneosition to lock the paw] and lever against ludependent movement.

8. In a motor compressor unit, comprising a cylinder and a pistonreciprocating in said cylinder a starting device comprising means forinject-ing from a reservoir compressed air behind the vmotor piston onthe compression side, said device comprising a cock, a piston loaded bya spring, a balanced valve connected to said piston and controlf ling aport in the cylinder. said cock admitting air from saidrreservor undersaid piston, and a non-return valve between said cock and said pistonand vents in said valve.

A motor compressor unit comprising a cylinder and a piston reciprocatingin said cylinder, one end portion of the cylinder bemg provided withafvalved air inlet, and a valved air outlet to said reservoir, the istonin its travel to this end of the cylin er being adapted to compress airand force same into the reservoir, the end of the cylinder beyond theoutlet to the reservoir confining air which serves as a gaseous buffer,the piston being returned by the expansion of this gaseous buffer, andmeans for limiting the maximum energy stored in this gaseous buffer.

10. A motor compressor unit comprising a. cylinder and a pistonreciprocating in said cylinder, a reservoir for ,air under pressure, oneend portion of the cylinder being, rovided with a valved air inlet, anda'va ved air outlet to said reservoir, the piston in its the cylinderbeing adapted to compress air the reservoir, the end of the cylinderbeyond the outlet to the reservoir confining air which serves as agaseous buffer, the iston being returned by the Vexpansion of thisgaseous buffer, and auxiliary connections b tween the reservoir and thisgaseous buffer.

11. A motor compressor unit comprisinga cylinder, a piston reciprocatingin said cylinder, and a main reservoir for compressed a reservoir forair under pressure,

and force same into air, a device for controlling the rate of thereciprocations of the piston, said device consisting. of an auxiliaryreservoir for compressed air, connections between said auxillaryreservoir andthe cylinder end on the compressor side, comprisingautomatic nonreturn valves. and` means for re-establishing in saidauxiliary reservoir, at each stroke, the pressure existing in the mainreservoir of the compressor.

12. A motor compressor unit, comprisin a cylinder and a pistonreciprocating in sai cylinder, a safety device adapted to prevent damageto the machine in case of an accidental collision between the piston`and the bottom of the cylinder, said device consist-ing in an elasticbutler mounted on thepiston an abutment on the head of the cylinder anan elastic connection between said head and said cylinder.

13. In a motor compressor unit comprisingl a cylinder and a pistonreciprocating in said cylinder, air inlets for the compressor, valvesfor said air inlets on the compressor side. and non-return valvesbetween said first-named valves and the atmosphere.

14. In an apparatus comprising a frame, a cylinder, a pistonreciprocating in said cylinder. said cylinder beingmechanically ree toreciprocate with respect to said frame, an auxiliary shaft. aquick-return'device connected to said shaft and to said cylinder andanelastic connection between said device and said cylinder.

15. In an apparatus comprising a frame, a cylinder, a pistonreciprocatingr in said cylinder, said cylinder being mechanically freeto reciprocate with respect to said frame; ports in said cylinder, tubesconnected to said ports, and communicating chambers on said frame. eachof vsaid tubes having a sliding air-tight it in one of said chambers, soas to form a Huid, circulating passage from said movable cylinder to anthrough said fixed chambers and thence back to the cylinder.

16. In an apparatus comprising a cylinder and a piston reciprocating insaid cylinder, a carburetter, inlet and outlet connections from saidcarburetter to one end portion of the cylinder, an air inlet in this endportion of the cylinder, valves in these connections, and automaticmeans for operating the valves whereby during the stroke of the pistoncarburetted air is admitted to the cylinder under low ressure, and pureair is drawnV in. the mixture is compressed on the succeedingcompression stroke of the piston, and a portion of this compressedmixture is returned to the carburetter for injection during the nextexpansion stroke.

In an apparatus com ising a cylinder and a piston reciprocating` in saidcylinder, a carburetter, a storage chamber communicating with thecarburetter, assages from thecylinder to the Stora e ciamber, and fromthe carburetter to t e cylinder, valves in these passages, and automaticmeans for operating the valves.

18. In an appara-tus comprising a cylinder, a frame, and a pistonreciprocatingln said cylinder, the cylinder being mounted` toreciprocate in the frame, a carburetter mounted on the frame. Huidassagesleading from one end portion o the cylinder to the carburetterand fromthe carburetter back to this end of the cylinder. and automaticvalves in the passages. the passages being extensible to permit themovement of the cylinder.

19. In an apparatus comprising a cylinder, a frame. and va istonreciprocating in said cylinder, theacyllnder being mounte to reciprocatein the frame, a carburetter mounted on the frame, a storage chambermounted on the frame and connected with the carburetter, a passage fromthe cylinder to the storage chamber. a passage from the carburetter tothe cylinder, valves in these passages, and means for controlling thevalves-operated by the movements of the cylinder. 4

20. In an apparatus comprising a cylinder, a frame. and a piston.reciprocating in said cylinderz the cylinder being mounted toreciprocate 1n the -frame, a carhuretter mounted on the frame, a storagechamber mounted on theframe and connected with the carburetter, apassage from the cylinder to the storage chamber, a passage fromthecarburetter to the cylinder, valves in these passages,.ixed camscarried by the frame, and meansY including rockers mounted on thecylinder and engaging the cams for controilin the valves. I y A 21. n' amotor compressor unit comprising a frame, a closed. cylinder, and apiston reciprocating in said cylinder, said cylinder being mechanicallyfree to reciprocate with respect to said frame; means for producing anexpansive force on one side of said piston within vsaid cylinder. imeans for simultaneously compressing air on the other side of saidpiston and means for discharging said compressed air at such a res-'sure that the reciprocal deadening o the relative movements between thecylinder and the piston is equal to the work of compression anddischarge of the air, less the work of restoring the piston and cylinderto their initial position.

' 22. In a motor compressor unit comprising a fra-me, a closed cylinderand .a V lston reciprocating in said cylinder, said cy inder beingmechanically free to reciprocate with respect to said frame, means forroducing an expansive force on one sde ofpsaid piston within saidcylinder, means for simultaneously compressing air on the other side ofsaid piston, means for dischargn a portion of said compressed air at suca pressure that the reciprocal deadening of the relative movementsbetween the cylinder and the piston is equal to the work of compressionand discharge of the air, and means for imprisoning the remainingportion of said compresse air between the piston and the correspondingcylinder end, at the same 'pressure so that its expansion may restorethe piston and cylinder to their initial position.

RAUL PATERAS PESCARA.

municating with the' carbnretter, assages from the .cylinder to thestorage c iarnber, and from the carburetter to the cylinder, valves inthese passages, and automatic means for operating the valves.

18. In an appara-tus comprising a cylinder, a frame, and a pistonreciprocating'ln said cylinder, the cylinder being mounted toreciprocate in the frame. a carbnretter mounted on the frame. Huidassages` leading from one end portion o the cylinder to the carburetterand fromthe carburetter back to this end of the cylinder. and automaticvalves in the passages. the passages being extensible to permit themovement of the cylinder.

19. In an apparatus comprising` a cylinder, a frame, and a istonreciprocating in said cylinder, the cylinder being mounted toreciprocate in the frame, a carbnretter mounted on the frame, a storagechamber mounted on the frame and connected with the carburetter. apassage from the cylinder to the storage chamber. a passage from thecarburetter to the cylinder, valves in these passages, and means forcontrolling the.

valvesoperated by the movements of the cylinder.

20. In an apparatus comprising a cylinder, a frame. and a iston.reciprocating in said cylinder, the cylinder being mounted toreciprocate 1n the --frame, a carburetter mounted on the frame, astorage chamber mounted on the'frame and connected with the carburetter,a passage from the cylinder to the storage chamber, a passage from thecarburetter to the cylinder, valves in these passages,.lixed camscarried by the frame, and means including rockers mounted on thecylinder and engaging the cams for controllin the valves. f

21. n a motor compressor unit comprising a frame` a closed. cylinder,and a piston reciprocating in said cylinder, said cylinder beingmechanically free to reciprocate with respect to said frame; means forproducing an expansive force on one side of said piston Within 4saidcylinder, means for simultaneously compressing air on the other side ofsaid piston and means for discharging said comp'rcssed air at such aressure that the reciprocal deadening o the relative movements betweenthe cylinder and the piston is equal to the work of compression anddischarge of the air, less the work of restoring the piston and cylinderto their initial position.

22. In 'a motor compressor unit comprisingr a frame, a closed cylinderand a iston reciprocating in said cylinder, said cy inder beingmechanically free to reciprocate with respect to said frame, means forroducing an expansive force on one side o? said piston within saidcylinder, means for simultaneously compressing air on the other side' ofsaid piston, means for discharginv a portion of said compressed air atsuc a pressure that the reciprocal deadening of the relative movementsbetween the cylinder and the piston is equal to the work of compressionand discharge of the air, and means for imprisoning the remainingportion of said compressed air between the piston and the correspondingcylinder end, at the same `pressure so that its expansion may restorethe piston and cylinder to their initial position.

RAUL PATEEAS PESCARA.

ce1-annu r common.

Pmi masacre?.

RAUL PATERAS PESCARA. It is herebyeertiedtliat errorappears in theprinted patent requx O correction -as follows: Page l ready f f and thatthe said' Letters Patent should be read with Granted May 24, 1927, to

ification of the aboveline 85, for the word this correction theremthatthe same may conform to the record ofthe in the sigma-.na salad'aasaan dq of June, A. D. im.

[um] v M. J. MOORE, Acting dominion# of Patente.

`Certicate of Correction. Patent bla/1,629,927. Granted May 24, 1927, toRAUL PATERAS PESCARA.

It is hereby certified that error'appears in the printed specificationof the abovenumbered Patent requiring correctxon `as follows: Page 9,line 851 for the word expl'ion read eagmlsoh; and that the said' LettersPatent should be rend with this correction therem that the same mayconform tothe record ofthe case in the Pat/ent Oiloe.

Signed and sealed this 28th day of June, A. D. 1927.

[BAL] l M. J. MOORE,

Acting Gomml'uioner of Patents.

